Fight­ing the myths be­hind the no­vac­ci­na­tion move­ment

Ac­cord­ing to a re­cent re­port by the Cen­ters for Dis­ease Con­trol and Pre­ven­tion, the num­ber of chil­dren with­out vac­cines is on the rise, and has been since at least 2001. The re­port finds that 1.3 per­cent of chil­dren born in 2015 were com­pletely un­vac­ci­nated, com­pared to 0.9 per­cent of chil­dren born in 2011 and 0.3 per­cent of chil­dren born in 2001. How wor­ried should we be?

Not that wor­ried, at least not yet. Vac­ci­na­tions pro­tect not just the chil­dren who re­ceive the shots, but ev­ery­one else as well. When enough of a given com­mu­nity gets vac­ci­nated, dis­eases can’t spread be­cause there aren’t enough un­vac­ci­nated peo­ple to catch the dis­ease, cre­at­ing what’s of­ten called “herd im­mu­nity.”

Herd im­mu­nity is an im­por­tant func­tion of vac­ci­na­tions. Some peo­ple can­not safely be vac­ci­nated be­cause of al­ler­gies or a weak im­mune sys­tem. Th­ese peo­ple have no choice but to rely on herd im­mu­nity. The herd im­mu­nity thresh­old de­pends on the dis­ease, but hy­per-con­ta­gious dis­eases like measles re­quire 90 per­cent to 95 per­cent vac­ci­na­tion lev­els for herd im­mu­nity to be ef­fec­tive.

As long as the num­ber of chil­dren with­out vac­ci­na­tions stays be­low 5 per­cent, you shouldn’t lose sleep wor­ry­ing about a measles epi­demic. Still, the trend of de­creas­ing per­cent­ages of vac­ci­nated chil­dren is con­cern­ing. Al­though herd im­mu­nity re­mains strong enough to pro­tect against large-scale out­breaks, cases of per­tus­sis and measles are on the rise be­cause of vac­cine opt-outs.

Peo­ple opt out of vac­ci­na­tions for var­i­ous rea­sons. Some, like Pres­i­dent Don­ald Trump, fear vac­cines cause autism (they don’t, as now-Health and Hu­man Ser­vices Sec­re­tary Ben Car­son tried to ex­plain to Trump dur­ing a 2016 cam­paign de­bate). Oth­ers worry about var­i­ous in­gre­di­ents found in some vac­cines, like alu­minum (none of th­ese are dan­ger­ous). An­other group protests on re­li­gious grounds.

It’s tempt­ing to say gov­ern­ment shouldn’t force peo­ple to get vac­cines, and that peo­ple de­serve the free­dom to make their own choices about vac­cines. But those who forgo vac­ci­na­tions aren’t just mak­ing choices for them­selves; they’re mak­ing choices for the vul­ner­a­ble pop­u­la­tions that rely on herd im­mu­nity.

This coun­try doesn’t al­low con­sci­en­tious ob­jec­tors to, say, ig­nore speed­ing laws. The rights of oth­ers to ex­ist in a safe en­vi­ron­ment su­per­sede those of the ob­jec­tors. When one per­son’s free­dom in­ter­feres with an­other’s safety, gov­ern­ments can and should in­ter­vene. A pub­lic school, for ex­am­ple, has ev­ery right to re­quire all stu­dents to re­ceive the rec­om­mended vac­cines be­fore en­rolling. Such manda­tory vac­cine poli­cies can go a long way to­ward pro­tect­ing the rest of the pop­u­la­tion from the rise in anti-vac­cine at­ti­tudes cur­rently driving down vac­ci­na­tion num­bers.